Acrylic acid purification tower C230 overhaul dehydration system
By adding a dehydration system to the acrylic acid production system and using hot nitrogen to evaporate the residual water, the problem of residual water being unable to be completely discharged after the acrylic acid purification tower C230 was overhauled was solved, the product quality was immediately qualified, and resource waste was reduced.
Patent Information
- Application Number
- CN202422507707.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-16
- Publication Date
- 2025-09-19
- Estimated Expiration
- 2034-10-16
AI Technical Summary
After overhaul, the acrylic acid purification tower C230 had residual water that could not be completely discharged, resulting in unqualified product quality in the initial stage of operation, causing a large number of unqualified products and waste of resources.
A dehydration system is added to the acrylic acid production system. Hot nitrogen is used to carry and evaporate residual water to perform system drying operations, and negative pressure dehydration is performed using the principle that the boiling point of water decreases with pressure.
It effectively avoids the problem of unqualified product quality in the initial stage of production, reduces the production of unqualified products, saves manpower, material and financial resources, and improves the qualified rate of product quality.
Smart Images
Figure CN223351028U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of acrylic acid product production, in particular to an acrylic acid purification tower C230 maintenance and dehydration system. Background Art
[0002] During actual production operation, the acrylic acid purification tower C230 will be shut down for regular maintenance due to the polymerization characteristics of acrylic acid materials. The polymer cleaning operation in the C230 tower will only be carried out after the water washing and ventilation replacement of the C230 system are qualified.
[0003] After the polymer cleanup was completed, residual water in the C230 tower system wasn't fully drained during the start-up phase, resulting in dead zones and water droplets clinging to the walls. This resulted in substandard acrylic acid product for approximately two days after the start-up due to excessive moisture content, resulting in approximately 1,000 tons of substandard product. After the system's moisture was replaced by the produced acrylic acid, the product returned to standard after approximately two days. These substandard acrylic acid products subsequently required refining or tankage, resulting in significant human, material, and financial resources. Utility Model Content
[0004] In order to address the deficiencies of the prior art, the utility model provides an acrylic acid purification tower C230 maintenance and dehydration system, which solves the problem of unqualified quality of acrylic acid products due to high water content after start-up.
[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an acrylic acid purification tower C230 maintenance dehydration system, comprising:
[0006] An acrylic acid production system is used to receive acrylic acid material and output acrylic acid product, and includes a C230 acrylic acid purification tower for receiving acrylic acid feed. The C230 acrylic acid purification tower establishes a conveying channel connected to the separation system through a connecting channel;
[0007] The dehydration system is used to provide a passage for transporting dehydrated gas to the acrylic acid production system. It includes an air supply channel connected to the transport channel. A circulating fan is installed on the extension trajectory of the air supply channel. The flow pipe connected to the circulating fan is connected to the C230 acrylic acid purification tower.
[0008] In one embodiment, the conveying channel includes an E232A / B tower top primary condenser connected to the communicating channel, a separator tank is provided at the lower end of the E232A / B tower top primary condenser, one end of the separator tank is connected to the E233 tower top secondary condenser for secondary condensation, and the output end of the E233 tower top secondary condenser is respectively conveyed to the separator tank and the water ring vacuum pump.
[0009] In one embodiment, the air supply channel is connected to the pipeline that supplies gas from the secondary condenser at the top of the E233 tower to the water ring vacuum pump, and the air supply channel is connected to a nitrogen input channel, and a nitrogen replenishment valve is provided on the nitrogen input channel for adjusting the nitrogen flow rate.
[0010] In one embodiment, a liquid outlet pipe is provided at the bottom of the C230 acrylic acid purification tower, and a bottom reboiler pump is connected to the installation position of the liquid outlet pipe. The output of the C230 acrylic acid purification tower enters the E231 reboiler after passing through the bottom reboiler pump, and the output of the E231 reboiler is transferred to the C230 acrylic acid purification tower.
[0011] In one embodiment, the nitrogen moves toward the circulation fan through the guidance of the air supply channel, and after passing through the circulation fan, the nitrogen moves toward the air supply pipe between the E231 reboiler and the tower bottom reboiler pump.
[0012] In one embodiment, the circulating fan is connected to a regulating valve and a vent valve for pressure relief connected in parallel with the regulating valve during the process of transporting nitrogen through the air supply pipe.
[0013] Compared with the prior art, the utility model provides an acrylic acid purification tower C230 maintenance dehydration system, which has the following beneficial effects:
[0014] In the technical solution disclosed by the utility model, a dehydration system is added to the acrylic acid production system. Before starting the production, the residual water in the system is carried out and evaporated by hot nitrogen to perform a system drying operation, thereby avoiding the problem of unqualified product quality and moisture in the early stage of production, avoiding the loss of manpower, material and financial resources caused by the re-refining or tank farm blending of thousands of tons of unqualified acrylic acid products, and improving the speed of product quality qualification, so that the material can be qualified on the same day it is put into production.
[0015] The utility model utilizes the principle that the boiling point of water decreases as the pressure decreases, and further dries the system by pumping negative pressure, thereby completely removing trace amounts of water vapor. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:
[0017] Figure 1 This is a schematic diagram of the overall structure of the utility model;
[0018] Figure 2 This is a schematic diagram of the structure of the acrylic acid production system of the utility model;
[0019] Figure 3 This is a schematic diagram of the structure of the dehydration system of the utility model.
[0020] In the figure: 1. Acrylic acid production system; 11. Acrylic acid purification tower; 12. Connecting channel; 13. Transport channel; 131. First-stage condenser at the top of the tower; 132. Separating tank; 133. Second-stage condenser at the top of the tower; 134. Water ring vacuum pump; 14. Liquid outlet pipe; 15. Reboiler pump at the bottom of the tower; 16. Reboiler; 17. Air supply pipe; 18. Drain valve; 2. Dehydration system; 21. Air supply channel; 22. Circulating fan; 23. Circulation pipeline; 24. Nitrogen input channel; 25. Nitrogen replenishment valve; 26. Control valve; 27. Vent valve. DETAILED DESCRIPTION
[0021] The following will describe the implementation methods of the present application in detail with reference to the accompanying drawings and examples, so that the implementation process of how the present application applies technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0022] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention.
[0023] Figure 1-Figure 3 This is an embodiment of the present invention. The specific problem addressed by this specific embodiment is that during actual production operation, the acrylic acid purification tower 11C230 will be regularly shut down for maintenance due to the polymerization characteristics of the acrylic acid material. The polymer cleaning operation in the C230 tower will only be carried out after the C230 system is washed and ventilated and replaced as qualified.
[0024] After the polymer cleaning is completed, during the start-up period, the residual water in the C230 tower system cannot be fully drained, resulting in dead zones of accumulated water and water droplets adhering to the wall. As a result, the quality of the acrylic acid product was unqualified for about 2 days after the start of operation due to the high water content, and about 1,000 tons of unqualified products were produced. When the water in the system was replaced by the produced acrylic acid for about 2 days, the product could be qualified. The subsequent 1,000 tons of unqualified acrylic acid products need to be recycled or blended in the tank area, resulting in a large waste of manpower, material resources and financial resources. Based on the above existing technical problems, this solution proposes a C230 maintenance and dehydration system for acrylic acid purification tower. A dehydration system 2 is added to the acrylic acid production system 1. Before the start of operation, the residual water in the system is carried and evaporated by hot nitrogen, and the system is dried to avoid the problem of unqualified product quality water in the initial stage of the start-up, and avoid the loss of manpower, material resources and financial resources caused by recycling or blending 1,000 tons of unqualified acrylic acid products in the tank area, thereby improving the rate of qualified product quality, and the material is qualified on the same day.
[0025] The acrylic acid purification tower C230 maintenance dehydration system described specifically includes: an acrylic acid production system 1, which is a normal working system for the purification of acrylic acid, and a dehydration system 2 added to the acrylic acid production system 1, which is used to address the existing technical problems. Before starting work, hot water for carrying and evaporating residual water is introduced into the normal acrylic acid production system 1 through the dehydration system 2 to perform a system drying operation, so that the material fed on the same day is qualified.
[0026] The acrylic acid production system 1 is used to receive the input of acrylic acid materials and output acrylic acid products. The dehydration system 2 is used to provide a passage for transporting dehydrated gas to the acrylic acid production system 1. It includes an air supply channel 21 connected to the transport passage. A C101 circulating fan 22 is installed on the extension track of the air supply channel 21. The flow pipe 23 connected to the C101 circulating fan 22 is connected to the C230 acrylic acid purification tower 11. The acrylic acid production system 1 includes a C230 acrylic acid purification tower 11 for receiving acrylic acid feed, the C230 acrylic acid purification tower 11 establishes a delivery channel 13 connected to the separation system through a connecting channel 12, the delivery channel 13 includes an E232A / B tower top primary condenser 131 connected to the connecting channel 12, a separator 132 is provided at the lower end of the E232A / B tower top primary condenser 131, one end of the separator 132 is connected to the E233 tower top secondary condenser 133 for secondary condensation, and the output end of the E233 tower top secondary condenser 133 is respectively The output of the C230 acrylic acid purification tower 11 is transported to a separatory tank 132 and a water ring vacuum pump 134. A liquid outlet pipe 14 is installed at the bottom of the C230 acrylic acid purification tower 11. A P230A / B tower kettle pump is installed on this outlet pipe 14. A tower bottom reboiler pump 15 is connected to the outlet pipe 14, offset from the installation position. After passing through the tower bottom reboiler pump 15, the output of the C230 acrylic acid purification tower 11 enters the E231 reboiler 16. The E231 reboiler 16 is connected to an FV001 steam regulating valve 26. The output of the E231 reboiler 16 is then transported to the C230 acrylic acid purification tower 11. A drain valve 18 is installed at the outlet pipe 14, the lower end of the separatory tank 132, and one end of the P233A / B tower bottom reboiler 16 pump. During normal maintenance, the acrylic acid production system 1 with the additional production dehydration system 2 is first checked for access, with the E233 tower top secondary condenser 133 → C101 circulating fan 22 → FV003 regulating valve 26 open → E231 reboiler 16 → C230 acrylic acid purification tower 11 → E232A / B tower top primary condenser 131 → E233 tower top secondary condenser 133 in an unobstructed state, the P216A / B / C water ring vacuum pump inlet manual valve closed, the P230A / B tower kettle pump inlet manual valve and drain valve 18 closed, the P233A / B tower bottom reboiler 16 pump inlet manual valve and drain valve 18 closed, and the FV004 vent regulating valve 26 closed. Then carry out the system pressure test, add nitrogen to the acrylic acid purification tower 11C230 system through the FV002 regulating valve 26, pressurize the C230 tower top PT231 to a slightly positive pressure of 5KPaG, and carry out an airtightness test. After passing the airtightness test, release the pressure to 1KPaG through the FV004 vent regulating valve 26. Repeat the operation for more than 3 times, take samples for testing and analysis, and the oxygen content of the system is less than 0.5%, so that the C230 system is in a qualified nitrogen environment.Based on the above, a cold nitrogen circulation system is established. Nitrogen is added to the system through nitrogen inlet channel 24, maintaining a slight positive pressure of 15 kPaG at the top of the C230 tower. The C101 circulating fan 22 is started according to the equipment unit requirements, and the system circulates nitrogen. After startup, the outlet pressure of the C101 circulating fan 22 is controlled at approximately 20 kPaG, with an outlet flow rate of approximately 6000-8000 Nm³ / h. The pressure at the top of the C230 tower is approximately 10 kPaG. If the system pressure is high, it is released through vent valve 27FV004. If the system pressure is low, it is added through nitrogen make-up valve 25FV002. After completing the above, the dehydration process begins.
[0027] The dehydration system 2 also includes an air supply channel 21 connected to the pipeline for transporting gas from the secondary condenser 133 at the top of the E233 tower to the water ring vacuum pump 134. The air supply channel 21 is connected to a nitrogen input channel 24. A nitrogen replenishing valve 25 is provided on the nitrogen input channel 24 for adjusting the nitrogen flow rate. The nitrogen replenishing valve 25 is an FV002 nitrogen replenishing valve 25. The nitrogen moves toward the C101 circulating fan 22 through the guidance of the air supply channel 21. After passing through the C101 circulating fan 22, the nitrogen moves toward the air supply pipe 17 between the E231 reboiler 16 and the tower bottom reboiler pump 15. In the process of the C101 circulating fan 22 transporting the nitrogen through the air supply pipe 17, a regulating valve 26 and a vent valve 27 for pressure relief connected in parallel with the regulating valve 26 are connected. The vent valve 27 is an FV 004 vent valve 27, regulating valve 26 is FV003 regulating valve 26, open E231 reboiler 16 steam regulating valve 26FV001, slowly heat up nitrogen at a rate of ≯20℃ / H until the outlet temperature of E231 reboiler 16 is about 103℃ and the tower top temperature is about 100℃. At this time, the liquid water in the system will vaporize, and the hot nitrogen will carry water vapor through the first-level condenser 131 at the top of C230 tower E232A / B tower and the second-level condenser 133 at the top of E233 tower for cooling and condensation, and gas-liquid separation will be carried out in D231 separator tank 132, and nitrogen will return to C101 circulation fan 22 for circulation. Continuously observe the rising situation of the liquid level in D231 separator tank 132, drain regularly, and at the same time, each shower valve 18 will drain every 2 hours. After 4 hours of hot nitrogen circulation, the surface of D231 separator tank 132 did not rise and no liquid was seen in each shower valve 18. It was judged that the hot nitrogen circulation was qualified and the moisture in the C230 system had been dried out. Then the hot nitrogen circulation was stopped and the P1216A / B / C water ring vacuum pump was started to extract the hot nitrogen from the system and reduce the negative pressure PT231 to -96KpaG. The trace water vapor in the hot nitrogen was discharged into the atmosphere and further removed to achieve the purpose of drying the system.
[0028] The control method of the present invention is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by technicians in this field. The provision of power is also common knowledge in this field. In addition, the present invention is mainly used to protect mechanical devices, so the control method and circuit connection are no longer explained in detail in the present invention.
[0029] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements that are inherent to such process, method, article or apparatus.
[0030] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. An acrylic acid purification tower C230 maintenance dehydration system, characterized in that: include: An acrylic acid production system (1) is used for receiving acrylic acid material and outputting acrylic acid product, and includes a C230 acrylic acid purification tower (11) for receiving acrylic acid feed, and the C230 acrylic acid purification tower (11) establishes a conveying channel (13) connected to a separation system through a connecting channel (12); The dehydration system (2) is used to provide a passage for conveying dehydrated gas to the acrylic acid production system (1), and includes an air supply channel (21) connected to the conveying channel, a circulating fan (22) is installed on the extension track of the air supply channel (21), and a flow pipe (23) connected to the circulating fan (22) is connected to the C230 acrylic acid purification tower (11).
2. The acrylic acid purification tower C230 maintenance and dehydration system according to claim 1, characterized in that: The delivery channel (13) includes an E232A / B tower top primary condenser (131) connected to the communication channel (12); a separatory tank (132) is provided at the lower end of the E232A / B tower top primary condenser (131); one end of the separatory tank (132) is connected to an E233 tower top secondary condenser (133) for secondary condensation; and the output end of the E233 tower top secondary condenser (133) is transported to the separatory tank (132) and the water ring vacuum pump (134) respectively.
3. The acrylic acid purification tower C230 maintenance and dehydration system according to claim 1, characterized in that: The air supply channel (21) is connected to the pipeline for conveying gas from the secondary condenser (133) at the top of the E233 tower to the water ring vacuum pump (134). The air supply channel (21) is connected to a nitrogen input channel (24). A nitrogen replenishment valve (25) is provided on the nitrogen input channel (24) for adjusting the nitrogen flow rate.
4. The acrylic acid purification tower C230 maintenance and dehydration system according to claim 1, characterized in that: The bottom of the C230 acrylic acid purification tower (11) is provided with a liquid outlet pipe (14), and a tower bottom reboiler pump (15) is connected to the installation position of the liquid outlet pipe (14). The output of the C230 acrylic acid purification tower (11) enters the E231 reboiler (16) after passing through the tower bottom reboiler pump (15), and the output of the E231 reboiler (16) is transmitted to the C230 acrylic acid purification tower (11).
5. The acrylic acid purification tower C230 maintenance and dehydration system according to claim 3, characterized in that: The nitrogen moves toward the circulation fan (22) through the guidance of the air supply channel (21), and then moves toward the air supply pipe (17) between the E231 reboiler (16) and the tower bottom reboiler pump (15) after passing through the circulation fan (22).
6. The acrylic acid purification tower C230 maintenance and dehydration system according to claim 5, characterized in that: During the process of the circulating fan (22) transporting nitrogen through the air supply pipe (17), a regulating valve (26) and a vent valve (27) for pressure relief connected in parallel with the regulating valve (26) are connected.